Views: 0 Author: Site Editor Publish Time: 2026-07-22 Origin: Site
400C Sol-Gel Ceramic-Like
Coating for Sheet Metal Enclosures（1）
What if your sheet metal enclosure could achieve the hardness of ceramic glass, the corrosion resistance of marine-grade coating, and the fire resistance needed for battery energy storage systems — all in a single 60-micron-thin layer?
DINGPRECISION is one of the few sheet metal manufacturers in China operating a dedicated 400C high-temperature curing liquid spraying line with a two-coat two-bake (2C2B) process capable of producing Sol-Gel ceramic-like coatings on SPCC, SGCC, and SECC substrates.
This page explains the technology, the science, and why it matters for your next project.
Unlike conventional organic coatings that cure at 80-200C through polymer cross-linking, our ceramic-like coating uses a Sol-Gel (Solution-Gelation) chemistry that cures at 400C, transforming liquid precursors into an inorganic Si-O-Si (silicon-oxygen-silicon) network — the same molecular structure found in glass and ceramics.
Our formulation uses organosilane precursors (TEOS + MTES/GPTMS) that undergo hydrolysis and condensation reactions:
Hydrolysis: Si(OC₂H₅)₄ + 4H₂O → Si(OH)₄ + 4C₂H₅OH
Condensation: Si-OH + HO-Si → Si-O-Si + H₂O
At 400C, these reactions complete to form a dense, continuous glass-ceramic hybrid network bonded chemically to the steel substrate via M-O-Si (metal-oxygen-silicon) bridges formed during our pre-treatment process (degreasing + zirconium-based conversion coating).
Property | Powder Coating | Conventional Liquid | DINGPRECISION Ceramic |
|---|---|---|---|
Curing Temperature | 180-200 C | 80-120 C | 400 C |
Pencil Hardness | 2H - 4H | H - 2H | 7H - 9H |
Salt Spray (NSS) | 500 - 720h | 500 - 1000h | 1000 - 2000h |
Coating Thickness | 80 - 120 um | 60 - 100 um | 50 - 70 um |
Thermal Shock Resistance | Poor (>150C cracks) | Moderate | Excellent (25C-375C) |
UV Resistance | Yellowing after 500h | Good (PU based) | Excellent (no degradation) |
Fire Resistance | None (organic burns) | Limited | Inherent (non-combustible) |
Adhesion (Cross-Hatch) | 0-1B (ASTM D3359) | 0-1B | 0B (chemical bonding) |
DINGPRECISION's ceramic-like coating line features a unique two-coat two-bake (2C2B) workflow:
Degreasing (alkaline cleaner, 50-60C, 5 min)
Zirconium-based conversion coating
Deionized water rinse + hot air dry
Air-assisted electrostatic or manual spray gun
Wet film thickness 80-120 um targeting 30-35 um dry
Flash-off 5-10 min ambient
Infrared pre-heating zone for rapid temperature rise
Hot air convection zone at 400C +/- 5C holding 12-18 min
Cooling zone at rate <10C/min
Masking first-color areas if dual-color required
Second coat application
Optional clear ceramic topcoat
Same profile as Step 3
Results in fully densified Si-O-Si network
Final inspection: thickness gauge, gloss meter, adhesion test
The 400C curing temperature is the minimum threshold at which Sol-Gel coatings transition from organic-inorganic hybrid to predominantly inorganic ceramic state:
Temperature Range | Coating State | Key Characteristics |
|---|---|---|
< 200C | Organic-rich hybrid | Flexible, moderate hardness |
200-350C | Transition zone | Organic decomposing, micro-crack risk |
400C +/- 20C | Optimal ceramic state | Full density, peak hardness 7H-9H |
> 450C | Over-sintering | Shrinkage stress, not recommended |
Most shops have ovens rated <=250C (for powder coating). Building to 400C requires:
Specialized refractory materials
IR heating elements with precise control
Capital investment: RMB 1-2 million
Lead time: 6-12 months
This creates a 12-18 month first-mover advantage for DINGPRECISION in the ceramic-coated sheet metal market.
